3D data objects: the data3d module

astra.data3d.change_geometry(i, geometry)[source]

Change the geometry of a 3D object.

Parameters:

  • i (int) – ID of object.

  • geometry (dict) – Volume or projection geometry.

astra.data3d.clear()[source]

Clear all 3D data objects.

astra.data3d.create(datatype, geometry, data=None)[source]

Create a 3D object.

Parameters:

  • datatype (string) – Data object type, ‘-vol’ or ‘-sino’.

  • geometry (dict) – Volume or projection geometry.

  • data (float or numpy.ndarray) – Data to fill the constructed object with, either a scalar or array.

Returns:

int – the ID of the constructed object.

astra.data3d.delete(ids)[source]

Delete a 3D object.

Parameters:

ids (int or list) – ID or list of ID’s to delete.

astra.data3d.dimensions(i)[source]

Get dimensions of a 3D object.

Parameters:

i (int) – ID of object.

Returns:

tuple – dimensions of object with ID i.

astra.data3d.get(i)[source]

Get a 3D object.

Parameters:

i (int) – ID of object to get. Linked GPU arrays are not supported.

Returns:

numpy.ndarray – The object data.

astra.data3d.get_geometry(i)[source]

Get the geometry of a 3D object.

Parameters:

i (int) – ID of object.

Returns:

dict – The geometry of object with ID i.

astra.data3d.get_shared(i)[source]

Get a 3D object with memory shared between the ASTRA toolbox and numpy array.

Parameters:

i (int) – ID of object to get. Linked GPU arrays are not supported.

Returns:

numpy.ndarray – The object data.

astra.data3d.get_single(i)[source]

Get a 3D object in single precision.

Parameters:

i (int) – ID of object to get. Linked GPU arrays are not supported.

Returns:

numpy.ndarray – The object data.

astra.data3d.info()[source]

Print info on 3D objects in memory.

Link a 3D array with ASTRA from another library supporting dlpack, such as numpy or pytorch.

Parameters:

  • datatype (string) – Data object type, ‘-vol’ or ‘-sino’.

  • geometry (dict) – Volume or projection geometry.

  • data (object) – Array to link. Needs to implement the dlpack protocol.

Returns:

int – the ID assigned to the linked object.

Added in version 2.2: Accept any 3D array supporting DLPack protocol. Before, only NumPy arrays were supported.

astra.data3d.shepp_logan(geometry, modified=True, returnData=True)[source]

Create a 3D data object with a Shepp-Logan phantom.

Parameters:

  • geometry – Volume geometry

  • modified – If False, generate the original Shepp-Logan phantom

  • returnData – If False, only return the ID of the new data object

Returns:

int or (int, :class`numpy.ndarray`)

Added in version 2.2.

astra.data3d.store(i, data)[source]

Fill existing 3D object with data.

Parameters:

  • i (int) – ID of object to fill. Linked GPU arrays are not supported.

  • data (float or numpy.ndarray) – Data to fill the object with, either a scalar or array.